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The London Underground

      The London Underground (also known simply as the Underground, or by its nickname the Tube) is a public rapid transit system serving London, England and some parts of the adjacent counties of Buckinghamshire, Essex and Hertfordshire in the United Kingdom.

    The Underground has its origins in the Metropolitan Railway, the world's first underground passenger railway. Opened in January 1863, it is now part of the Circle, Hammersmith & City and Metropolitan lines; the first line to operate underground electric traction trains, the City & South London Railway in 1890, is now part of the Northern line. The network has expanded to 11 lines, and in 2017/18 carried 1.357 billion passengers, making it the world's 11th busiest metro system. The 11 lines collectively handle up to 5 million passengers a day.

      Despite its name, only 45% of the system is underground in tunnels, with much of the network in the outer environs of London being on the surface.

      As of 2015, 92% of operational expenditure is covered by passenger fares.  

Early years 

     The idea of an underground railway linking the City of London with the urban centre was proposed in the 1830s, and the Metropolitan Railway was granted permission to build such a line in 1854. To prepare construction, a short test tunnel was built in 1855 in Kibblesworth, a small town with geological properties similar to London. This test tunnel was used for two years in the development of the first underground train, and was later, in 1861, filled up. The world's first underground railway opened in January 1863 between Paddington and Farringdon using gas-lit wooden carriages hauled by steam locomotives.

     While steam locomotives were in use on the Underground there were  I  health reports. There were many instances of passengers collapsing whilst travelling, due to heat and pollution, leading for calls to clean the air through the installation of garden plants. The Metropolitan even encouraged beards for staff to act as an air filter. There were other reports claiming beneficial outcomes of using the Underground, including the designation of Great Portland Street as a "sanatorium for [sufferers of ...] asthma and bronchial complaints", tonsillitis could be cured with acid gas and the Twopenny Tube cured anorexia.

       During the war many tube stations were used as air-raid shelters. On 3 March 1943, a test of the air-raid warning sirens, together with the firing of a new type of anti-aircraft rocket, resulted in a crush of people attempting to take shelter in Bethnal Green Underground station. A total of 173 people, including 62 children, died, making this both the worst civilian disaster of World War II, and the largest loss of life in a single incident on the London Underground network.

      A different kind of accident occurred on 28 February 1975, a southbound train on the Northern City Line failed to stop at its Moorgate terminus and crashed into the wall at the end of the tunnel, in the Moorgate tube crash. There were 43 deaths and 74 injuries, the greatest loss of life during peacetime on the London Underground.

    A few years later, on 18 November 1987, fire broke out in an escalator at King's Cross St. Pancras tube station. The resulting fire cost the lives of 31 people and injured a further 100. London Underground were strongly criticised in the aftermath for their attitude to fires underground, and publication of the report into the fire led to the resignation of senior management of both London Underground and London Regional Transport. To comply with new safety regulations issued as a result of the fire, and to combat graffiti, a train refurbishment project was launched in July 1991. 

(Adapted from: https://en.wikipedia.org)